Box van rear end mod

[j-c-c]

The difference is in this discussion, what you are noting is a single use approval, vs an overall design "use" approval, but again, that is only a guess.

So are noting the Calif to Evergreen move, or the initial "water effect" flight move by Howard?

[aerohead]

Originally Posted by j-c-c

The difference is in this discussion, what you are noting is a single use approval, vs an overall design "use" approval, but again, that is only a guess.

So are noting the Calif to Evergreen move, or the initial "water effect" flight move by Howard?

Yes, under the umbrella of the U.S. Department of Energy, any trucker is permitted to add up to 60-inches length to a rig, if it's for energy conservation. No questions asked.
With respect to the 'Spruce Goose,' it was trailered from Culver City, to Los Angeles Harbor and assembled for the flight.
In 1971 it was next door to the Queen Mary, in Long Beach. I was guessing that for the move north, that it was de-winged and trailered north. Please accept my apology if that's incorrect.

[aerohead]

Originally Posted by Engeu1

I think the CD is around .37 for my vehicle, versus .32 for the Sprinter panel van.

Ask uncle google for images of 'sprinter luton van' and you'll get the idea.

Okay, thanks ! Looks like she has challenges with the sides and belly, and some images show at least two iterations between the back of the cab door and the beginning of the box sides leading edges. Wheel arch gaps are something some will obsess over now.
The Sprinter has the 'Stromform' nose developed in the 1980s. FIAT developed a bus which used it to achieve Cd 0.238 by 1980. They referred to it as the 'ideal' nose.

[freebeard]

Imagine a building big enough that the Spruce Goose is lost in it.


Oregon’s Evergreen Aviation & Space Museum Features Spruce Goose and Titan II Missile | Airport Journals

The pieces were barged up the Willamette from Portland, through the locks at Oregon City. The Spruce Goose Moves to McMinnville, Oregon – August 16, 2014 | Robert Novell

Here's my attempt at a boat-tail design from 2013:

It could be limited to 60". The bows would be fiberglass rods. The flat floor makes for a rigid diffuser roof.

[Engeu1]

Originally Posted by aerohead

. This tail, however, was optimized for a 'box' or 'van' which already had upper edge radii, something not seen typically in commercial vehicles, due to the intrusion into the cargo volume.

I have radii on the sides at the top, but all rear edges are square.

Originally Posted by aerohead

Hucho tested vanes and measured no benefits. Only box-cavities and boat-tails made any difference.

If fairly or unfairly we put the following in the category of vanes, how would you put the respective fuel economy or drag reduction claims in context vis-a-vis Hucho?

See II Air Foils | School Buses

https://rocketail.com

https://www.researchgate.net/publica...al_Guide_Vanes

(there are full copies of the last paper available online via search)

[Engeu1]

Originally Posted by freebeard

It could be limited to 60".

Unfortunately I don't have anywhere near that much to make use of. So the solution needs to be relatively simple, and short or 'clipped'.

In practice, I think you have much more freedom for changes in the US than in most European countries. That's for a number of reasons, plus I also have limits because of practical considerations.

[Engeu1]

Originally Posted by aerohead

Okay, thanks ! Looks like she has challenges with the sides and belly, and some images show at least two iterations between the back of the cab door and the beginning of the box sides leading edges. Wheel arch gaps are something some will obsess over now.
The Sprinter has the 'Stromform' nose developed in the 1980s. FIAT developed a bus which used it to achieve Cd 0.238 by 1980. They referred to it as the 'ideal' nose.

There is a proper integrated deflector at the front over the cab, but a side gap which will get looked at later on. It's the same basic body as the Volkswagen Crafter (if you know that).

[freebeard]

Unfortunately I don't have anywhere near that much to make use of. So the solution needs to be relatively simple, and short or 'clipped'.

This is what I thought works before I started lurking on EcoModder. A chamfer, sort of a 'bullet-tail'.


https://ecomodder.com/forum/showthre...ail-33283.html

This is from Morelli. Instead of max camber at 30% of the length it has it at the rear putting the whole body in a favorable pressure gradient. Pending aerohead's agreement.

[Engeu1]

So this:





https://www.shell.com/business-custo...monstrate.html

is not what I'm aiming for....quite.

[Engeu1]

Originally Posted by freebeard

This is what I thought works before I started lurking on EcoModder. A chamfer, sort of a 'bullet-tail'.


https://ecomodder.com/forum/showthre...ail-33283.html

This is from Morelli.

I've read that the convergence angle can't go much beyond 16 degrees without breakaway, hence the v.g. idea.